I have a motor home that is leaking black & gray water sewage through the top vent connections on the black water & grey water Polyethylene tanks. The ABS Vent pipe 3/8" flanges were screwed to the top of the tank with tiny metal screws that rusted away. The top of the tanks are only 3.5" below the floor above so the working space is very limited.

I think I need a slow setting putty like substance that I can shape & mold around these 2" ABS vent pipes to prevent the effluent from spilling out when making turns.

This has become a consistent problem for me because this portion of these tanks are in a sealed basement compartment where I used to store an open top tool box, hence rusty, stinky tools, too many times!!

Upon the recommendation from a store clerk I recently used a product named water weld. It was EZ to work with & looked pretty good when finished. It seemed to stick pretty well to the black (ABS?) Pipe BUT did not stick to the top of the Polyethylene tank.

It took another trip & clean-up to learn that it didn't work after-all.

I thought I did a good job in cleaning these surfaces but did not use any sanding components thereon.

The instructions mentions “Surfaces to be repaired do not need to be clean and dry” so my prep should have been OK.

I contacted the Motorhome Mfg first & they recommend rough sanding with 40/60 grit sandpaper & using a 2 part epoxy but my past experience with epoxy sticking to plastic has not been very good.

Can you please recommend a product that will do this job.

Thanks a million!!

--WOODY--
Semper Fi



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